In this paper we deal with the question of when the norm of a Kubo–Ando mean σ
determines the order on the positive definite cone of an operator algebra. More precisely, we …

We prove that any bijective map between the positive definite cones of von Neumann
algebras which preserves a certain unitarily invariant norm of a particular weighted …

Maps on Hilbert space effect algebras preserving norms of operator means Page 1 Acta
Scientiarum Mathematicarum 84:1–2 (2018) c Bolyai Institute, University of Szeged doi …

In this paper, we determine the general form of transformations on positive operators
preserving ap-norm of a power mean with positive exponent. The corresponding theorems …

In this paper, we mainly discuss the problem of describing the structure of transformations
leaving norms of generalized weighted quasi-arithmetic means of invertible positive …

We consider three operations on the positive definite cones of C∗-algebras which are
Schatten p-norm of various versions of the quantum Rényi relative entropy. The main results …

We study bijective transformations ϕ of the set of positive operators on a Hilbert space such
that given a Kubo-Ando mean σ with certain properties,‖ A σ B‖=‖ ϕ (A) σ ϕ (B)‖ holds …

We consider the spectrum-preserving maps on positive definite cones of C*-algebras or von
Neumann algebras. We first introduce some basic properties of Jordan isomorphism. Then …

The topic of the dissertation falls into the area of preserver problems. The dissertation
consists of five chapters followed by a summary (both in English and in Hungarian) and a …

A jelen disszertáció néhány eredményt tartalmaz a megorzési problémák területérol. Az
ilyen problémákat általánosan a következoképpen tudjuk megfogalmazni. Legyen adott egy …